I received some new LEDs this week and I soldered another module together with a new high intensity blue/red bi-color LED. I decided to put about 5mA through each of them, not knowing how bright they would be. After assembly, I measured the currents: 3.8mA through the blue LED and 5.0mA through the red LED for a total of 8.8mA... and still sooo much light. That means I can design for an ever lower current and probably cut about another 4-5mA out of the power budget. :)
The picture shows all three modules I have built so far (I had to turn down the sensitivity in order not to blind the camera with the LEDs):
- On the left, module #1:
Green/orange bi-color LED (orange shows, but green and orange LED are on simultaneously, orange overwhelming the green)
- On the right, module #2:
Blue LED
- In the center, module #3:
Blue/red bi-color LED (purple shows, blue and red simultaneously about the same intensity)
Sadly enough, my multi-meter pin shorted to Vcc when measuring the red LED, so it died :( I have some de-soldering to do tonight and fix it.
I also changed the charge resistor for the on-board battery to a lower value so as to recharge that battery a little faster (without exceeding the maximum charge current of course).
Module #3 is also using a slightly smaller patch antenna (see the center module in the photo) of about 13x13x4mm compared to the 15x15x4mm ones that I used for the other modules. I took the module out to the store while on my way buying a digital calipers for the housing design. The module performed above expectation, which is a good foresight for the next PCB board which will be using a chip antenna. It would be great if I can freeze the next design, as the form factor is very small and it has a full dock connector on it. If it doesn't perform well, I have to go back to a patch antenna and a micro-USB port in order to keep the module as small as possible.
Also this week I have made some more new contacts with local contract manufacturers, both for the PCB and the plastic housing. My main next priority is coming up with a final drawing for the housing design so that I can have prototypes made of it.
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